Carriage of media content quality information

ABSTRACT

Technology for communicating Moving Picture Experts Group (MPEG)-2 streaming video quality information is disclosed. A network element can generate quality access units that are associated with one or more media access units in a media content stream representation. The quality access units can indicate quality metadata for the media access units in the media content stream representation. The network element can encapsulate the quality access units in an MPEG-2 transport stream (TS). The network element can generate a quality extension descriptor that describes the quality metadata indicated in the quality access units. The network element can communicate, to a user equipment (UE), the quality extension descriptor according to a defined periodicity. The network element can communicate, to the UE, the quality access units in the MPEG TS with the media access units, wherein the quality access units are interpreted at the UE based on the quality extension descriptor.

RELATED APPLICATIONS

The present application claims priority to U.S. Provisional PatentApplication No. 62/063,845, filed Oct. 14, 2014, with a docket number ofP74791Z, the entire specification of which is hereby incorporated byreference in its entirety for all purposes.

BACKGROUND

The growth of multimedia services, including streaming andconversational services, is one of the key drivers of the evolution tonew mobile broadband technologies and standards. Digital video contentis increasingly consumed in mobile devices. There are many videoapplications extensively used on mobile devices in daily life. Forexample, online video streaming include popular services such as YouTubeand Hulu. Video recording and video conferencing include services suchas Skype and Google Hangout. In 2011, YouTube had more than 1 trillionglobal views. Ten percent of the views were accessed via mobile phonesor tablets. As more smart phones, tablets, and other mobile computingdevices are purchased, their use for video recording and videoconferencing will increase dramatically. With such high consumer demandfor multimedia services coupled with developments in media compressionand wireless network infrastructures, it is of interest to enhance themultimedia service capabilities of future cellular and mobile broadbandsystems and deliver high quality of experience (QoE) to the consumers,thereby ensuring ubiquitous access to video content and services fromany location, at any time, with any device and technology.

BRIEF DESCRIPTION OF THE DRAWINGS

Features and advantages of the disclosure will be apparent from thedetailed description which follows, taken in conjunction with theaccompanying drawings, which together illustrate, by way of example,features of the disclosure; and, wherein:

FIG. 1 illustrates an Moving Picture Experts Group (MPEG)-2 transportstream (TS) format in accordance with an example;

FIG. 2 illustrates signaling between a network element and a userequipment (UE) to communicate Moving Picture Experts Group (MPEG)-2streaming video quality information in accordance with an example;

FIG. 3 illustrates carriage of quality metadata over an Moving PictureExperts Group (MPEG)-2 transport stream (TS) in accordance with anexample;

FIG. 4 illustrates a delivery of quality metadata in a Moving PictureExperts Group (MPEG)-2 transport stream (TS) format in accordance withan example;

FIG. 5 is a table of identifier (ID) assignment values in accordancewith an example;

FIG. 6 is a table of extension descriptors in accordance with anexample;

FIG. 7 is a table of extension descriptor tag values in accordance withan example;

FIG. 8 illustrates a transcoder configured to receive an InternationalOrganization for Standardization (ISO) base media file format (ISOBMFF)file or an MPEG-2 TS file as input and provide quality metadata forMPEG-2 TS or quality metadata for an ISOBMFF file as an output inaccordance with an example;

FIG. 9 illustrates an abstract syntax notation (ASN) code example of adynamic adaptive streaming over hypertext transfer protocol (DASH) mediapresentation description (MPD) file in which a carriage of qualityinformation based on a an Moving Picture Experts Group (MPEG)-2transport stream (TS) format is signaled via a codecs parameter inaccordance with an example;

FIG. 10 depicts functionality of a network element operable tocommunicate Moving Picture Experts Group (MPEG)-2 streaming videoquality information in accordance with an example;

FIG. 11 depicts functionality of a user equipment (UE) operable toperform media content playback using media content quality informationin accordance with an example;

FIG. 12 depicts a flow chart of at least one non-transitory machinereadable storage medium having instructions embodied thereon forreceiving Moving Picture Experts Group (MPEG)-2 streaming video qualityinformation at a user equipment (UE) in accordance with an example; and

FIG. 13 illustrates a diagram of a wireless device (e.g., UE) inaccordance with an example.

Reference will now be made to the exemplary embodiments illustrated, andspecific language will be used herein to describe the same. It willnevertheless be understood that no limitation of the scope of theinvention is thereby intended.

DETAILED DESCRIPTION

Before the present invention is disclosed and described, it is to beunderstood that this invention is not limited to the particularstructures, process steps, or materials disclosed herein, but isextended to equivalents thereof as would be recognized by thoseordinarily skilled in the relevant arts. It should also be understoodthat terminology employed herein is used for the purpose of describingparticular examples only and is not intended to be limiting. The samereference numerals in different drawings represent the same element.Numbers provided in flow charts and processes are provided for clarityin illustrating steps and operations and do not necessarily indicate aparticular order or sequence.

Example Embodiments

An initial overview of technology embodiments is provided below and thenspecific technology embodiments are described in further detail later.This initial summary is intended to aid readers in understanding thetechnology more quickly but is not intended to identify key features oressential features of the technology nor is it intended to limit thescope of the claimed subject matter.

A technology is described for communicating Moving Picture Experts Group(MPEG)-2 streaming video quality information. A network element cangenerate quality access units that are associated with one or more mediaaccess units in a media content stream representation. The media accessunits can be media content frames (e.g., video frames) in the mediacontent stream representation. The quality access units can indicatequality metadata (e.g., quality metrics) for the media access units inthe media content stream representation. In other words, each qualityaccess unit can indicate quality metadata for one or more media accessunits (or media content frames). The network can encapsulate the qualityaccess units in a Moving Picture Experts Group (MPEG)-2 transport stream(TS). The network element can generate a quality extension descriptorthat describes the quality metadata indicated in the quality accessunits. The network element can communicate the quality extensiondescriptor in a program map table (PMT) to a user equipment (UE)according to a defined periodicity (e.g., approximately every 100milliseconds). In addition, the network element can communicate thequality access units in the MPEG TS to the UE. The quality access unitscan be communicated to the UE with the media access units in the mediacontent stream representation. The UE can parse and decode the MPEG TSusing the quality extension descriptor in order to extract the qualityaccess units (and the quality metadata). The UE can present, via a mediaplayer that is executing at the UE, the media access units based on thequality metadata included in the quality access units. In other words,the UE can utilize the quality metadata in the MPEG-2 TS tointelligently stream the media access units in the media content streamrepresentation.

There have been a number of multimedia standards that have beendeveloped to enable multimedia to be communicated to, from, or betweencomputing devices. For instance, in streaming video, the thirdgeneration partnership project (3GPP) has developed technicalspecification (TS) 26.234 (e.g. Release 11.0.0) that describespacket-switched streaming services (PSS) that are based on the real-timestreaming protocol (RTSP) for unicast streaming of on-demand or livecontent. In addition, hyper-text transfer protocol (HTTP) basedstreaming services, including progressive download and dynamic adaptivestreaming over HTTP (DASH), are described in 3GPP TS 26.247 (e.g.Release 11.0.0). 3GPP-based multimedia broadcast and multicast services(MBMS) specification TS 26.346 (e.g. Release 11.0.0) specifies streamingand download techniques for multicast/broadcast content distribution. Assuch, DASH/PSS/MBMS-based mobile computing devices, such as userequipment (UEs), decode and render streamed videos at the UE devices.Support for the 3GPP file format in 3GPP TS 26.244 (e.g. Release 11.0.0)is mandated in all of these specifications to support file download andHTTP-based streaming use cases.

Multimedia streaming in a high mobility environment can be challengingwhen fluctuations in network conditions (i.e., network variability)decreases a communication data rate associated with the multimediacontent. When an overloaded network causes the communication data rateto decrease, an end user quality of experience (QoE) can decrease aswell. For example, the multimedia content received at the mobile devicecan be of less resolution or quality and/or the multimedia content canperiodically break or pause when being provided over the overloadednetwork.

Multimedia content that is streamed to a client, such as a userequipment (UE), can include a plurality of multimedia content segments.The multimedia content segments can each contain different encodedversions that represent different qualities levels of the multimediacontent. The different encoded versions can allow the client toseamlessly adapt to changing network conditions. For example, when thenetwork conditions are good (i.e., the network conditions are above apredetermined threshold), the client can request multimedia contentsegments that are of a higher video quality. When the network conditionsare poor (i.e., the network conditions are below a predeterminedthreshold), the client can request multimedia content segments that areof a lower video quality. As a result, the client may still be able toreceive the multimedia content segments (albeit at a lower quality) whenthe network conditions are poor and a likelihood of the adaptive mediastream being interrupted can be reduced.

Some media streaming technologies, such as DASH, currently support theinclusion of timed metadata. The timed metadata can be periodicallyincluded in a media content stream that is provided to the client.Examples of timed metadata include quality information and indicatorsfor power reduction. The quality information in the timed metadata canenable the client to achieve smoother quality streaming and reducedbandwidth consumption. In one example, the client can use the qualityinformation (or quality metadata) to intelligently select which encodedversion of the media content is to be received at the client in order tomaximize streaming quality and bandwidth consumption. The qualitymetadata can be associated with media content segments that are beingreceived at the client.

The quality metadata can dynamically indicate a quality level for themedia content segments. In one example, if the quality metadataindicates that the quality level for the media content segments isrelatively low (e.g., the video is grainy), the client can request mediacontent segments of an increased quality level (albeit at a higherbitrate). In another example, if the quality metadata indicates that thequality level for the media content segments is relatively high, theclient can request media content segments at a slightly lower qualitylevel (which can result in a reduced bitrate), such that the reducedquality level is not substantially noticeable to the client's user. Inother words, if a reduction of quality is not noticeable to the user,then media content segments at a reduced quality level can be selectedin order to save bandwidth. As previously stated, the quality metadataprovided to the client can enable the client to intelligently requestthe media content segments for playback.

The Moving Picture Experts Group (MPEG)-2 transport stream (TS) is amedia format that is deployed in a number of systems (e.g., broadcastsystems), such as digital video broadcasting (DVB) and AdvancedTelevision Systems Committee (ATSC). In previous solutions, the MPEG2-TSformat does not support the carriage of video quality metrics andassociated metadata. As a result, traditional systems based on MPEG2-TSformats (e.g., broadcasts) cannot realize the benefits of quality-drivenadaptive streaming. In addition, during transcoding operations, it waspreviously not possible to translate quality information due to lack ofsupport in the MPEG2-TS format. An example of a transcoding operationcan include transcoding from an International Organization forStandardization (ISO) base media file format (ISOBMFF) to the MPEG2-TSfile format, or vice versa.

The technology described herein relates to the carriage of video qualitymetadata in the MPEG2-TS media file format. As a result, the benefits ofquality-driven adaptive streaming can be applied to MPEG2-TS systems. Inaddition, the translation of quality information during transcodingoperations (e.g., from ISOBMFF to MPEG2-TS, or vice versa) can beenabled with the present technology.

FIG. 1 illustrates an exemplary Moving Picture Experts Group (MPEG)-2transport stream (TS) format. Video data can be provided to a videoencoder 105. The video encoder 105 can produce encoded video data, whichis then provided to a first packetizer 115. The first packetizer 115 cangenerate video Packetized Elementary Stream (PES) packets from theencoded video data. In addition, audio data can be provided to an audioencoder 110. The audio encoder 110 can produce encoded audio data, whichis then provided to a second packetizer 120. The second packetizer 120can generate audio Packetized Elementary Stream (PES) packets from theencoded audio data. In one example, the video PES packets and the audioPES packets can be provided to a program stream (PS) multiplexer 125,which generates a program stream to include the video PES packets andthe audio PES packets. In another example, the video PES packets and theaudio PES packets can be provided to a transport stream (TS) multiplexer130, which generates a transport stream to include the video PES packetsand the audio PES packets.

The MPEG-2 TS is a standard container format that is used for thetransmission and storage of audio, video and Program and SystemInformation (PSIP) data. The container format (or wrapper format) candescribe how different elements of data and metadata coexist in acomputer file. In one example, the MEPG-2 TS can include metadata (e.g.,quality metadata) that describes the audio/video. The MPEG-2 TS can beused in broadcast systems, such as DVB, ATSC, and Internet ProtocolTelevision (IPTV). The MPEG-2 TS is further defined in MPEG-2 Part 1,Systems (formally known as ISO/IEC standard 13818-1 or ITU-T Rec.H.222.0). The IEC is also referred to as the InternationalElectrotechnical Commission. The MPEG-2 TS can specify the containerformat for encapsulating the packetized elementary streams (with errorcorrection), as well as stream synchronization features for maintainingtransmission integrity when the signal is degraded. The transport streamcan differ from the program stream in several ways. The program streamis designed for reasonably reliable media, such as discs (e.g., DVDs),while the transport stream is designed for less reliable transmission,such as terrestrial or satellite broadcast. In addition, the transportstream can carry multiple programs.

The MPEG-2 transport stream can include program-specific information(PSI), which is metadata about a certain program (or channel). Oneexample of PSI is a program map table (PMT). The PMT can includeinformation about programs. For instance, a transport stream used indigital television might contain three programs to represent the threetelevision channels. The three programs (or channels) can be describedby three PMTs. Each channel can include one video stream, one or twoaudio streams, and metadata. The PMTs can provide information on eachprogram present in the transport stream, including a program number, andlist the elementary streams that are included in the described MPEG-2program.

FIG. 2 illustrates exemplary signaling between a network element 210 anda user equipment (UE) 220 to communicate Moving Picture Experts Group(MPEG)-2 streaming video quality information. The network element 210can be located in a content delivery network (CDN) or an operatornetwork. The network element 210 can stream media content to the UE 220.As used herein, the term “media content” can refer to audio and/orvideo. The network element 210 can send video quality information to theUE 220 along with the media content. The video quality information candescribe a quality level for one or more media content frames includedin the media content. The video quality information (e.g., qualitymetadata) can enable the UE 220 to intelligently request media contentframes from the network element 210 based on the video qualityinformation. For example, the UE 220 can adapt a media content bitrate,resolution and/or frame rate based on the video quality informationreceived from the network element 210. As a result, the UE 220 can bequality aware when receiving media content in accordance with the MPEG-2standard.

In one example, the network element 210 can generate quality accessunits that are associated with one or more media access units (or videoframes) in a media content stream representation. The media access unitscan be media content frames (e.g., video frames) in the media contentstream representation. The quality access units can indicate qualitymetadata for the media access units in the media content streamrepresentation. The quality metadata can include quality metrics for themedia access units. As a non-limiting example, a particular qualityaccess unit (with quality metadata) can be associated with a sequence offive media access units (or five media content frames). In general, thequality access units can be dynamic information that reflects variationsin the quality levels of the media access units in a timely manner. Inother words, since the quality access units can be sent for each mediaaccess unit, a change in quality level can be quickly reflected inchanged metadata in a subsequent quality access unit.

In one example, the quality access units can be associated with aparticular media content stream. Multiple media content streams can bebroadcasted by the network element 210 at a given time, so the UE 220 isto know which media content stream corresponds to the quality accessunits. In addition, the UE 220 is to know which media access unit (ormedia content frame) is being described by a particular quality accessunit. This information can be indicated in the quality access format.

As previously explained, the quality access units can include qualitymetadata. The quality metrics included in the quality metadata can beobjective or subjective criteria used to judge a quality level of themedia content frame. In general, media content quality (or videoquality) refers to a formal or informal measure of perceived mediacontent degradation between original media content and the media contentafter its passed through a media content transmission or processingsystem (e.g., a video encoder). In other words, the quality metric canmeasure a difference between an original media content signal, which isgenerally considered to be of high quality (since the original mediacontent signal is not compressed) and the encoded (or otherwisetransformed) media content signal. In one example, the quality metricsincluded in the quality metadata can include a signal-to-noise ratio(SNR), peak signal-to-noise ratio (PNSR), a structural similarity index(SSIM), a multi-scale structural similarity index (MS-SSIM), a videoquality metric (VQM), a perceptual evaluation of video quality (PEVQ), amean opinion score (MOS), a frame significance (FSIG), a CzenakowskiDistance (CZD), etc.

In one configuration, a quality access unit is an access unit thatcontains dynamic quality metadata, as defined in ISO/IEC 23001-10.Therefore, dynamic quality metadata can be stored in access units thatare associated with one or more media content frames (e.g., videoframes). These access units can be encapsulated in MPEG sections, whichare identified by a stream type value of 0x2C. Each quality access unitcan contain configuration and timing information, as well as an array ofquality metric values. The quality values can have a one-to-onecorrespondence to the quality metrics. Each quality metric value can bepadded by preceded zero bytes, as needed, to the number of bytesindicated by a field size bytes parameter. A quality access unit can bein accordance with the following syntax:

Syntax No. Bits Mnemonic Quality_Access_Unit( ) { field_size_bytes 8uimsbf metric_count 8 uimsbf for ( i = 0; i < metric_count; i++) {metric_code 32 uimsbf sample_count 8 uimsbf for ( j = 0; j <sample_count; j++) { ‘0010’ 4 bslbf media_DTS [32..30] 3 uimsbfmarker_bit 1 bslbf media_DTS [29..15] 15 uimsbf marker_bit 1 bslbfmedia_DTS [14..0] 15 uimsbf marker_bit 1 bslbf quality_metric_sample N }} }

With respect to the syntax of the quality access unit, the field sizebytes (or field_size_bytes) parameter can indicate a size of a qualitymetric sample field. The metric count (or metric_count) parameter canindicate a number of quality metric values in each quality access unit.The metric code (or metric_code) parameter can indicate a code name forquality metric values in the quality access units. The sample count (orsample_count) parameter can indicate a number of quality metric samplesper quality metric value. The decoding time stamp (DTS) parameter, ormedia_DTS, can indicate a DTS of the media access unit that is describedby a quality metric sample.

In one example, the network element 210 can encapsulate the qualityaccess units in a Moving Picture Experts Group (MPEG)-2 transport stream(TS). The MPEG-2 TS is a standard container format that is used for thetransmission of audio, video and metadata. In other words, the qualityaccess units can be carried in MPEG sections. Each quality access unitcan be a random access point. In addition, each quality access unit canbe contained in a single transport stream (TS) packet.

In one example, the network element 210 can generate a quality extensiondescriptor that describes the quality metadata indicated in the qualityaccess units.

The quality extension descriptor can be sent to the UE 220 once perevent or program. The quality extension descriptor can be signaled usinga descriptor in a program map table (PMT). The PMT is an entity that isperiodically sent from the network element 210 to the UE 220. The PMT isan electronic service guide that informs the UE 220 of the media contentto be transmitted to the UE 220. This descriptor can appear in anelementary stream loop of the packet identifier (PID) for which thequality information is provided. The quality extension descriptor candescribe quality metrics that are present in each quality access unit.The quality extension descriptor can include a constant field size thatis used for quality metric values. In other words, the quality extensiondescriptor can enable the UE 220 to process the quality metadata that isincluded in the quality access units. The UE 220 might not know how tointerpret the quality metadata if the quality extension descriptor isnot received from the network element 210, and as a result, the UE 220might ignore the quality metadata in this scenario (i.e., when the UE220 does not receive the quality extension descriptor). The qualitymetrics can be further described in ISO/IEC 23001-10.

In one example, the quality extension descriptor can be in accordancewith the following syntax:

Syntax No. bits Mnemonic QUALITY_extension_descriptor( ) {descriptor_tag 8 Uimsbf field_size_bytes 8 Uimsbf metric_count 8 Uimsbffor (i=0; i < metric_count; i++) metric_code[i] 32 Uimsbf }

With respect to the syntax of the quality extension descriptor, thedescriptor tag (or descriptor_tag) parameter can indicate a tag of thequality extension descriptor. The field size bytes (or field_size_bytes)parameter can indicate a constant size (in bytes) for quality metricvalues in each quality access unit. The metric count (or metric_count)parameter can indicate a number of quality metric values in each qualityaccess unit. The metric code (or metric_code) parameter can indicate acode name for quality metric values in the quality access units.Optionally, the syntax of the quality extension descriptor can include astream identifier (or stream_id) parameter, which indicates a streamidentifier for the media content stream representation that is describedby the quality access units. The semantics for these syntax elements arespecified in ISO/IEC 23001-10.

In one example, the network element 210 can communicate to the UE 220the quality extension descriptor in the PMT. The network element 210 cansend the quality extension descriptor according to a definedperiodicity. In one example, the network element 210 can send thequality extension descriptor approximately every 100 milliseconds (ms).In general, the quality extension descriptor can be more staticinformation that is sent to the UE 220. The UE 220 can interpret a groupof media access units (e.g., the media access units received in a 100 mstimeframe) based on the quality extension descriptor. The UE 220 caninterpret a subsequent group of access units based on a subsequentquality extension descriptor. The quality extension descriptor can be ageneral descriptor that is potentially applied to hundreds of qualityaccess units. On the other hand, the quality access units can be moredynamic because they are associated with one or several media contentframes (e.g., on the order of tens of milliseconds of video).

The network element 210 can communicate the quality access units in theMPEG TS to the UE 220. In addition, the network element 210 cancommunicate the media access units in the media content streamrepresentation to the UE 220. In other words, the media access units canbe communicated in conjunction with the corresponding quality accessunits. The MPEG standard describes a packetization format, which appliesto the media access units (or video frames) and the quality accessunits. The media access units and the quality access units aretransmitted in band to the UE 220. On the other hand, the qualityextension descriptor (which is included in the PMT) is out-of-bandinformation. The quality extension descriptor can be transmitted to theUE 220 separately from the media access units and the quality accessunits.

In one example, the UE 220 can receive the quality extension descriptor,the media access units, and the quality access units (that isencapsulated in the MPEG-2 TS) from the network element 210. In oneexample, the UE 220 can receive multiple quality extension descriptorsand associated quality access units that correspond to multiple mediacontent stream representations in a single MPEG-2 TS. The UE 220 canparse the MPEG TS in order to extract the quality access units. The UE220 can decode the quality access units in order to identify the qualitymetadata included in the quality access units. In one example, the UE220 can use the quality extension descriptor to parse and decode theMPEG-2 TS in order to extract the quality access units, as well as thequality metadata that is included in the quality access units. In otherwords, the previous transmission of the quality extension descriptorfrom the network element 210 can enable the UE 220 to access the qualitymetadata. The UE 220 may be unable to access the quality metadata if thequality extension descriptor was not previously received from thenetwork element 210. In the scenario when the UE 220 does not have thequality extension descriptor, the UE 220 may simply ignore the qualitymetadata included in the MPEG-2 TS. In order to maintain backwardscompatibility, legacy UEs may ignore the quality metadata, whereas newerUEs that are quality aware may utilize the quality metadata during mediacontent playback.

In one example, the UE 220 can include a demultiplexer to process theMPEG-2 TS. Since the MPEG-2 TS is a multiplexed format, the audio,video, metadata (e.g., quality access units), etc. can be packagedtogether. In other words, the audio, video and metadata are multiplexed,packetized and transmitted over a medium from the network element 210 tothe UE 220. The demultiplexer can identify the audio, the video and themetadata. At this time, the UE 220 can parse and decode the metadata(e.g., the metadata that includes the quality access units) using thequality extension descriptor in order to extract the quality metadatafrom the metadata.

The UE 220 can provide the media access units and the quality metadatato a media content player of the UE 220. The media content player can beconfigured to initiate playback of the media access units. The qualitymetadata can be provided to the media content player (e.g., a DASHMPEG-2 media player). The media player can use the quality metadata indeciding which media content frames to request going forward and how toadapt the streaming media content going forward. In one example, themedia player can adapt a media content bitrate, a resolution or a framerate based on the quality metadata.

In one example, the media player of the UE 220 can request media contentframes that have an increased quality level (albeit at a higherbitrate). In another example, if the quality metadata indicates that thequality level for the media content frames is relatively high, the mediaplayer can request media content frames at a slightly lower qualitylevel (which can result in a reduced bitrate), such that the reducedquality level is not substantially noticeable to the UE's user. In otherwords, if a reduction of quality is not noticeable to the user, thenmedia content frames at a reduced quality level can be selected in orderto save bandwidth. Therefore, the use of quality metadata at the mediaplayer can enable the UE to intelligently request the media contentframes for playback.

In one configuration, the quality access unit and the media access unitcan be in accordance with a defined timing relationship. A qualitymetadata can share a same media timeline with associated media accessunits. The quality metadata can be associated with one or more videoframes. The quality access unit can be decoded, and decoded informationcan be made available to the UE 220 before the corresponding mediaaccess unit is fetched from the network element 210. Such a timingrelationship can guarantee that the quality metadata within the qualityaccess u nit is made available to the UE 220 with sufficient lead timerelative to a request time and presentation time stamp (PTS) of anassociated media access unit. The PTS of the media access unit and thePTS of the quality access unit can be identical. The quality access unitcan be transmitted in the transport stream with a sufficient lead time,such that suitable media adaptations (e.g., bitrate, resolution, framerate) can be performed in advance of the presentation time of theassociated media access unit.

FIG. 3 illustrates carriage of quality metadata over an Moving PictureExperts Group (MPEG)-2 transport stream (TS). FIG. 3 illustrates anMPEG-2 program 310 with associated metadata. The MPEG-2 310 program canbe associated with audio 322 and video 324. The MPEG-2 program 310 canbe described by a program map table (PMT) 320, which has a unique packetidentifier (PID). The elementary streams that are associated with theMPEG-2 program 310 can have PIDs that are listed in the PMT 320. The PMT320 can include a content labeling descriptor 322 and a quality metadatapointer descriptor 324. The content labeling descriptor 322 can point toa content label 330. The content label 330 can be referenced by ametadata service 360. The quality metadata pointer descriptor 324 can bepoint to a quality metadata descriptor 326. The quality metadatadescriptor 326 in the PMT 320 can also be referred to as a qualityextension descriptor. The quality metadata descriptor 326 can point to ametadata service ID 328. The MPEG-2 program 310 can include a metadatastream 355. The metadata stream 355 can include quality metadata for oneor more frames in the video 340. Therefore, the video 340, audio 350 andthe metadata stream 355 (e.g., which contains the quality metadata) canbe multiplexed in the MPEG-2 program 310.

FIG. 4 illustrates a delivery of quality metadata in a Moving PictureExperts Group (MPEG)-2 transport stream (TS) format. The MPEG-2 TS caninclude audio and video (A/V) content 410. The A/V content 410 can beprovided from a network element to a user equipment (UE). While the A/Vcontent 410 is being provided to the UE, metadata (e.g., qualitymetadata) can be periodically sent with the A/V content 410. In oneexample, the A/V content 410 can include a first packet time stamp(PTS1) that is associated with a first quality metadata, a second packettime stamp (PTS2) that is associated with a second quality metadata, anda third packet time stamp (PTS3) that is associated with a third qualitymetadata. In other words, a packet time stamp can be substantiallyidentical to a corresponding quality metadata. The UE can receive theA/V content 410, as well as the quality metadata associated with the A/Vcontent 410, and can adaptively stream the A/V content 410 based on thequality metadata. For example, the UE can request an increased bitrateor a decreased bitrate based on the quality metadata that is received inthe MEPG-2 TS.

FIG. 5 is an exemplary table of identifier (ID) assignment values. TheID assignment values for MPEG2-TS formats can be included in Table 2-31of ISO/IEC 13818-1. In one example, the table can include a value of0x0A and an associated description of “ISO/IEC 23001-10 (Quality AccessUnit) section”.

In one configuration, Table 2-34 of ISO/IEC 13818-1 (not shown in FIG.5) can include a value of 0x2C and an associated description of “QualityStream access units carried in sections”. In addition, Table 2-34 ofISO/IEC 13818-1 can include a value of 0x2D-0x7E and an associateddescription of “ITU-T Rec. H.222.0 |ISO/IEC 13818-1 reserved”.

In one configuration, Table T-1 of ISO/IEC 13818-1 (not shown in FIG. 5)can include ‘codecs’ parameter values. As an example, a stream typeidentified as 0x2C can be associated with an element identified as“Vqme”.

FIG. 6 is an exemplary table of extension descriptors. The extensiondescriptors can be included in Table 2-103bis in Clause 2.6.90 ofISO/IEC 13818-1. The table can include a quality extension descriptorthat is noted as Quality_extension_descriptor( ).

FIG. 7 is an exemplary table of extension descriptor tag values. Theextension descriptor tag values can be included in Table 2-103ter inClause 2.6.91 of ISO/IEC 13818-1. The table can include a qualityextension descriptor, also referred to as Quality_extension_descriptor(). The quality extension descriptor can be associated with an extensiondescriptor tag value of 9. The quality extension descriptor can beapplicable to a transport stream (TS) and not applicable to a packetstream (PS). In addition, the structure of the quality extensiondescriptor can be defined in ISO/IEC 13818-1 Clauses 2.6.104 and2.6.105.

FIG. 8 illustrates an exemplary transcoder 810 configured to receive anInternational Organization for Standardization (ISO) base media fileformat (ISOBMFF) file or an MPEG-2 TS file as input and provide qualitymetadata for MPEG-2 TS or quality metadata for an ISOBMFF file as anoutput. In one example, the transcoder 810 can receive the ISOBMFF file,decode the ISOBMFF file, and translate quality metadata in the ISOBMFFfile in order to generate the quality metadata for the MPEG-2 TS. Inother words, the quality metadata extracted from the ISOBMFF file can beused for the MPEG-2 TS. In another example, the transcoder 810 canreceive an MPEG-2 TS file, decode the MPEG-2 TS file, and translatequality metadata in the MPEG-2 TS file in order to generate qualitymetadata to be communicated using the ISOBMFF file. In other words, thequality metadata extracted from the MPEG-2 TS file can be used for theISOBMFF file. The quality metadata to be communicated over the ISOBMFFfile can be associated with an MPEG-2 TS based media content streamrepresentation, wherein the quality metadata includes quality metricvalues for one or more media content frames in the MPEG-2 TS based mediacontent stream representation.

FIG. 9 illustrates an exemplary abstract syntax notation (ASN) codeexample of a dynamic adaptive streaming over hypertext transfer protocol(DASH) media presentation description (MPD) file. The carriage ofquality information based on a an Moving Picture Experts Group (MPEG)-2transport stream (TS) format can be signaled via a codecs parameter (or@codecs parameter) in the DASH MPD file. The codecs parameter canindicate a value of “vqme.psnr”. In this example, the video qualitymetrics can be based on peak signal to noise ratio (PSNR). A completeset of codec names for different video quality metrics and associatedmetadata can be found in ISO/IEC 23001-10.

Another example provides functionality 1000 of a network elementoperable to communicate Moving Picture Experts Group (MPEG)-2 streamingvideo quality information, as shown in the flow chart in FIG. 10. Thefunctionality can be implemented as a method or the functionality can beexecuted as instructions on a machine, where the instructions areincluded on at least one computer readable medium or one non-transitorymachine readable storage medium. The network element can comprise one ormore processors configured to generate quality access units that areassociated with one or more media access units in a media content streamrepresentation, the quality access units indicating quality metadata forthe media access units in the media content stream representation, as inblock 1010. The one or more processors can be configured to encapsulatethe quality access units in a Moving Picture Experts Group (MPEG)-2transport stream (TS), as in block 1020. The one or more processors canbe configured to generate a quality extension descriptor that describesthe quality metadata indicated in the quality access units, as in block1030. The one or more processors can be configured to communicate, to auser equipment (UE), the quality extension descriptor according to adefined periodicity, as in block 1040. The one or more processors can beconfigured to communicate, to the UE, the quality access units in theMPEG TS with the media access units in the media content streamrepresentation, wherein the quality access units are interpreted at theUE based on the quality extension descriptor, as in block 1050.

In one configuration, a first processor can perform the operations inblocks 1010, 1020 and/or 1030. The first processor can be a singleprocessor, or alternatively, the first processor can be comprised of oneor more separate processors. In one configuration, a second processorcan perform the operations in blocks 1040 and/or 1050. One example ofthe second processor is a baseband processor.

In one example, the quality access units in the MPEG TS and the mediaaccess units are communicated to the UE to enable the UE to parse theMPEG TS using the quality extension descriptor to extract the qualityaccess units, decode the quality access units and present the mediaaccess units based on the quality access units. In another example, thequality metadata includes at least one of the following quality metricvalues: a peak signal to noise ratio (PSNR); a structural similarityindex (SSIM); a multi-scale structural similarity index (MS-SSIM); avideo quality metric (VQM); a perceptual evaluation of video quality(PEVQ); a mean opinion score (MOS); or a frame significance (FSIG).

In one example, the quality extension descriptor includes at least oneof: a number of quality metric values in each quality access unit; aconstant size for quality metric values in each quality access unit; acode name for quality metric values in the quality access units; or astream identifier for the media content stream representation that isdescribed by the quality access units. In another example, the one ormore processors are further configured to: send multiple qualityextension descriptors and associated quality access units thatcorrespond to multiple media content stream representations using asingle MPEG-2 TS.

In one example, each quality access unit includes at least one of: anumber of quality metric values; a size of a quality metric samplefield; a code name for the quality metric values; a number of qualitymetric samples per quality metric value; or a decoding time stamp (DTS)of the media access unit that is described by a quality metric sample.In another example, the one or more processors are further configured touse a transcoder to parse an International Organization forStandardization (ISO) base media file format (ISOBMFF) file, decode theISOBMFF file, and translate quality metadata in the ISOBMFF file inorder to generate the quality metadata for the MPEG-2 TS.

In one example, the one or more processors are further configured to usea transcoder to parse an MPEG-2 TS file, decode the MPEG-2 TS file, andtranslate quality metadata in the MPEG-2 TS file in order to generatequality metadata to be communicated from the network element over anInternational Organization for Standardization (ISO) base media fileformat (ISOBMFF) file. In another example, the quality metadata to becommunicated over the ISOBMFF file is associated with an MPEG-2 TS basedmedia content stream representation, wherein the quality metadataincludes quality metric values for one or more media content frames inthe MPEG-2 TS based media content stream representation.

In one example, the quality extension descriptor is included in aprogram map table (PMT) and is communicated to the UE approximatelyevery 100 milliseconds (ms). In another example, the media access unitsare media content frames (e.g., media content frames) in the mediacontent stream representation. In yet another example, presentation timestamps of the quality access units are substantially identical topresentation time stamps of the media access units.

Another example provides functionality 1100 of a user equipment (UE)operable to perform media content playback using media content qualityinformation, as shown in the flow chart in FIG. 11. The functionalitycan be implemented as a method or the functionality can be executed asinstructions on a machine, where the instructions are included on atleast one computer readable medium or one non-transitory machinereadable storage medium. The UE can comprise one or more processorsconfigured to receive, at the UE, a quality extension descriptor from anetwork element that describes quality metadata in quality access units,the quality access units being associated with one or more media accessunits in a media content stream representation to be received at the UE,as in block 1110. The one or more processors can be configured toreceive, from the network element, the quality access units in a MovingPicture Experts Group (MPEG)-2 transport stream (TS) with the mediaaccess units in the media content stream representation, as in block1120. The one or more processors can be configured to identify, at theUE, the quality metadata from the quality access units in the MPEG-2 TSbased on the quality extension descriptor, as in block 1130. The one ormore processors can be configured to provide the media access units andthe quality metadata to a media content player of the UE to initiate themedia content playback, wherein the media content player is configuredto adapt at least one of: a media content bitrate, a resolution or aframe rate based on the quality metadata, as in block 1140.

In one configuration, a first processor can perform the operations inblocks 1110 and/or 1120. One example of the first processor is abaseband processor. In one configuration, a second processor can performthe operations in blocks 1130 and/or 1140. The second processor can be asingle processor, or alternatively, the second processor can becomprised of one or more separate processors.

In one example, the quality metadata includes at least one of thefollowing quality metric values: a peak signal to noise ratio (PSNR); astructural similarity index (SSIM); a multi-scale structural similarityindex (MS-SSIM); a video quality metric (VQM); a perceptual evaluationof video quality (PEVQ); a mean opinion score (MOS); or a framesignificance (FSIG). In another example, the quality extensiondescriptor includes at least one of: a number of quality metric valuesin each quality access unit; a constant size for quality metric valuesin each quality access unit; a code name for quality metric values inthe quality access units; or a stream identifier for the media contentstream representation that is described by the quality access units.

In one example, the one or more processors are further configured to:receive multiple quality extension descriptors and associated qualityaccess units that correspond to multiple media content streamrepresentations in a single MPEG-2 TS. In another example, each qualityaccess unit includes at least one of: a number of quality metric values;a size of a quality metric sample field; a code name for the qualitymetric values; a number of quality metric samples per quality metricvalue; or a decoding time stamp (DTS) of the media access unit that isdescribed by a quality metric sample.

Another example provides functionality 1200 of at least onenon-transitory machine readable storage medium having instructionsembodied thereon for receiving Moving Picture Experts Group (MPEG)-2streaming video quality information at a user equipment (UE), as shownin the flow chart in FIG. 12. The instructions, when executed, can causethe UE to perform receiving, using at least one processor of the UE, aquality extension descriptor from a network element that describesquality metadata in quality access units, the quality access units beingassociated with one or more media access units in a media content streamrepresentation to be received at the UE, as in block 1210. Theinstructions, when executed, can cause the UE to perform receiving,using at least one processor of the UE, from the network element thequality access units in a Moving Picture Experts Group (MPEG)-2transport stream (TS) with the media access units in the media contentstream representation, as in block 1220. The instructions, whenexecuted, can cause the UE to perform extracting, using at least oneprocessor of the UE, the quality metadata from the quality access unitsin the MPEG-2 TS based on the quality extension descriptor, wherein thequality metadata is used during playback of the media access units atthe UE, as in block 1230.

In one example, the at least one non-transitory machine readable storagecan further comprise instructions which when executed by the at leastone processor of the UE, cause the UE to perform the following:providing the media access units and the quality metadata to a mediacontent player of the UE to initiate the playback of the media accessunits, wherein the media content player is configured to adapt at leastone of: a media content bitrate, a resolution or a frame rate based onthe quality metadata.

In one example, the quality extension descriptor is received at the UEfrom the network approximately every 100 milliseconds (ms), wherein thequality extension descriptor is included in a program map table (PMT).In another example, the at least one non-transitory machine readablestorage medium can further comprise instructions which when executed bythe at least one processor of the UE, cause the UE to perform thefollowing: decoding, at the UE, a quality access unit before acorresponding media access unit is fetched from the network element

FIG. 13 provides an example illustration of the wireless device, such asa user equipment (UE), a mobile station (MS), a mobile wireless device,a mobile communication device, a tablet, a handset, or other type ofwireless device. The wireless device can include one or more antennasconfigured to communicate with a node or transmission station, such as abase station (BS), an evolved Node B (eNB), a baseband unit (BBU), aremote radio head (RRH), a remote radio equipment (RRE), a relay station(RS), a radio equipment (RE), a remote radio unit (RRU), a centralprocessing module (CPM), or other type of wireless wide area network(WWA/V) access point. The wireless device can be configured tocommunicate using at least one wireless communication standard including3GPP LTE, WiMAX, High Speed Packet Access (HSPA), Bluetooth, and WiFi.The wireless device can communicate using separate antennas for eachwireless communication standard or shared antennas for multiple wirelesscommunication standards. The wireless device can communicate in awireless local area network (WLA/V), a wireless personal area network(WPA/V), and/or a WWA/V.

FIG. 13 also provides an illustration of a microphone and one or morespeakers that can be used for audio input and output from the wirelessdevice. The display screen can be a liquid crystal display (LCD) screen,or other type of display screen such as an organic light emitting diode(OLED) display. The display screen can be configured as a touch screen.The touch screen can use capacitive, resistive, or another type of touchscreen technology. An application processor and a graphics processor canbe coupled to internal memory to provide processing and displaycapabilities. A non-volatile memory port can also be used to providedata input/output options to a user. The non-volatile memory port canalso be used to expand the memory capabilities of the wireless device. Akeyboard can be integrated with the wireless device or wirelesslyconnected to the wireless device to provide additional user input. Avirtual keyboard can also be provided using the touch screen.

Various techniques, or certain aspects or portions thereof, can take theform of program code (i.e., instructions) embodied in tangible media,such as floppy diskettes, compact disc-read-only memory (CD-ROMs), harddrives, non-transitory computer readable storage medium, or any othermachine-readable storage medium wherein, when the program code is loadedinto and executed by a machine, such as a computer, the machine becomesan apparatus for practicing the various techniques. Circuitry caninclude hardware, firmware, program code, executable code, computerinstructions, and/or software. A non-transitory computer readablestorage medium can be a computer readable storage medium that does notinclude signal. In the case of program code execution on programmablecomputers, the computing device can include a processor, a storagemedium readable by the processor (including volatile and non-volatilememory and/or storage elements), at least one input device, and at leastone output device. The volatile and non-volatile memory and/or storageelements can be a random-access memory (RAM), erasable programmable readonly memory (EPROM), flash drive, optical drive, magnetic hard drive,solid state drive, or other medium for storing electronic data. The nodeand wireless device can also include a transceiver module (i.e.,transceiver), a counter module (i.e., counter), a processing module(i.e., processor), and/or a clock module (i.e., clock) or timer module(i.e., timer). One or more programs that can implement or utilize thevarious techniques described herein can use an application programminginterface (API), reusable controls, and the like. Such programs can beimplemented in a high level procedural or object oriented programminglanguage to communicate with a computer system. However, the program(s)can be implemented in assembly or machine language, if desired. In anycase, the language can be a compiled or interpreted language, andcombined with hardware implementations.

As used herein, the term processor can include general purposeprocessors, specialized processors such as VLSI, FPGAs, or other typesof specialized processors, as well as base band processors used intransceivers to send, receive, and process wireless communications.

It should be understood that many of the functional units described inthis specification have been labeled as modules, in order to moreparticularly emphasize their implementation independence. For example, amodule can be implemented as a hardware circuit comprising customvery-large-scale integration (VLSI) circuits or gate arrays,off-the-shelf semiconductors such as logic chips, transistors, or otherdiscrete components. A module can also be implemented in programmablehardware devices such as field programmable gate arrays, programmablearray logic, programmable logic devices or the like.

In one example, multiple hardware circuits can be used to implement thefunctional units described in this specification. For example, a firsthardware circuit can be used to perform processing operations and asecond hardware circuit (e.g., a transceiver) can be used to communicatewith other entities. The first hardware circuit and the second hardwarecircuit can be integrated into a single hardware circuit, oralternatively, the first hardware circuit and the second hardwarecircuit can be separate hardware circuits.

Modules can also be implemented in software for execution by varioustypes of processors. An identified module of executable code can, forinstance, comprise one or more physical or logical blocks of computerinstructions, which can, for instance, be organized as an object,procedure, or function. Nevertheless, the executables of an identifiedmodule need not be physically located together, but can comprisedisparate instructions stored in different locations which, when joinedlogically together, comprise the module and achieve the stated purposefor the module.

Indeed, a module of executable code can be a single instruction, or manyinstructions, and can even be distributed over several different codesegments, among different programs, and across several memory devices.Similarly, operational data can be identified and illustrated hereinwithin modules, and can be embodied in any suitable form and organizedwithin any suitable type of data structure. The operational data can becollected as a single data set, or can be distributed over differentlocations including over different storage devices, and can exist, atleast partially, merely as electronic signals on a system or network.The modules can be passive or active, including agents operable toperform desired functions.

Reference throughout this specification to “an example” or “exemplary”means that a particular feature, structure, or characteristic describedin connection with the example is included in at least one embodiment ofthe present invention. Thus, appearances of the phrases “in an example”or the word “exemplary” in various places throughout this specificationare not necessarily all referring to the same embodiment.

As used herein, a plurality of items, structural elements, compositionalelements, and/or materials can be presented in a common list forconvenience. However, these lists should be construed as though eachmember of the list is individually identified as a separate and uniquemember. Thus, no individual member of such list should be construed as ade facto equivalent of any other member of the same list solely based ontheir presentation in a common group without indications to thecontrary. In addition, various embodiments and example of the presentinvention can be referred to herein along with alternatives for thevarious components thereof. It is understood that such embodiments,examples, and alternatives are not to be construed as defactoequivalents of one another, but are to be considered as separate andautonomous representations of the present invention.

Furthermore, the described features, structures, or characteristics canbe combined in any suitable manner in one or more embodiments. In thefollowing description, numerous specific details are provided, such asexamples of layouts, distances, network examples, etc., to provide athorough understanding of embodiments of the invention. One skilled inthe relevant art will recognize, however, that the invention can bepracticed without one or more of the specific details, or with othermethods, components, layouts, etc. In other instances, well-knownstructures, materials, or operations are not shown or described indetail to avoid obscuring aspects of the invention.

While the forgoing examples are illustrative of the principles of thepresent invention in one or more particular applications, it will beapparent to those of ordinary skill in the art that numerousmodifications in form, usage and details of implementation can be madewithout the exercise of inventive faculty, and without departing fromthe principles and concepts of the invention. Accordingly, it is notintended that the invention be limited, except as by the claims setforth below.

What is claimed is:
 1. A network element operable to communicate Moving Picture Experts Group (MPEG)-2 streaming video quality information, the network element comprising one or more processors configured to: generate quality access units that are associated with one or more media access units in a media content stream representation, the quality access units indicating quality metadata for the media access units in the media content stream representation; encapsulate the quality access units in a Moving Picture Experts Group (MPEG)-2 transport stream (TS); generate a quality extension descriptor that describes the quality metadata indicated in the quality access units; communicate, to a user equipment (UE), the quality extension descriptor according to a defined periodicity; and communicate, to the UE, the quality access units in the MPEG TS with the media access units in the media content stream representation, wherein the quality access units are interpreted at the UE based on the quality extension descriptor.
 2. The network element of claim 1, wherein the quality access units in the MPEG TS and the media access units are communicated to the UE to enable the UE to parse the MPEG TS using the quality extension descriptor to extract the quality access units, decode the quality access units and present the media access units based on the quality access units.
 3. The network element of claim 1, wherein the quality metadata includes at least one of the following quality metric values: a peak signal to noise ratio (PSNR); a structural similarity index (SSIM); a multi-scale structural similarity index (MS-SSIM); a video quality metric (VQM); a perceptual evaluation of video quality (PEVQ); a mean opinion score (MOS); or a frame significance (FSIG).
 4. The network element of claim 1, wherein the quality extension descriptor includes at least one of: a number of quality metric values in each quality access unit; a constant size for quality metric values in each quality access unit; a code name for quality metric values in the quality access units; or a stream identifier for the media content stream representation that is described by the quality access units.
 5. The network element of claim 1, wherein the one or more processors are further configured to: send multiple quality extension descriptors and associated quality access units that correspond to multiple media content stream representations using a single MPEG-2 TS.
 6. The network element of claim 1, wherein each quality access unit includes at least one of: a number of quality metric values; a size of a quality metric sample field; a code name for the quality metric values; a number of quality metric samples per quality metric value; or a decoding time stamp (DTS) of the media access unit that is described by a quality metric sample.
 7. The network element of claim 1, wherein the one or more processors are further configured to use a transcoder to parse an International Organization for Standardization (ISO) base media file format (ISOBMFF) file, decode the ISOBMFF file, and translate quality metadata in the ISOBMFF file in order to generate the quality metadata for the MPEG-2 TS.
 8. The network element of claim 1, wherein the one or more processors are further configured to use a transcoder to parse an MPEG-2 TS file, decode the MPEG-2 TS file, and translate quality metadata in the MPEG-2 TS file in order to generate quality metadata to be communicated from the network element over an International Organization for Standardization (ISO) base media file format (ISOBMFF) file.
 9. The network element of claim 8, wherein the quality metadata to be communicated over the ISOBMFF file is associated with an MPEG-2 TS based media content stream representation, wherein the quality metadata includes quality metric values for one or more media content frames in the MPEG-2 TS based media content stream representation.
 10. The network element of claim 1, wherein the quality extension descriptor is included in a program map table (PMT) and is communicated to the UE approximately every 100 milliseconds (ms).
 11. The network element of claim 1, wherein the media access units are media content frames in the media content stream representation.
 12. The network element of claim 1, wherein presentation time stamps of the quality access units are substantially identical to presentation time stamps of the media access units.
 13. A user equipment (UE) operable to perform media content playback using media content quality information, the UE comprising one or more processors configured to: receive, at the UE, a quality extension descriptor from a network element that describes quality metadata in quality access units, the quality access units being associated with one or more media access units in a media content stream representation to be received at the UE; receive, from the network element, the quality access units in a Moving Picture Experts Group (MPEG)-2 transport stream (TS) with the media access units in the media content stream representation; identify, at the UE, the quality metadata from the quality access units in the MPEG-2 TS based on the quality extension descriptor; and provide the media access units and the quality metadata to a media content player of the UE to initiate the media content playback, wherein the media content player is configured to adapt at least one of: a media content bitrate, a resolution or a frame rate based on the quality metadata.
 14. The UE of claim 13, wherein the quality metadata includes at least one of the following quality metric values: a peak signal to noise ratio (PSNR); a structural similarity index (SSIM); a multi-scale structural similarity index (MS-SSIM); a video quality metric (VQM); a perceptual evaluation of video quality (PEVQ); a mean opinion score (MOS); or a frame significance (FSIG).
 15. The UE of claim 13, wherein the quality extension descriptor includes at least one of: a number of quality metric values in each quality access unit; a constant size for quality metric values in each quality access unit; a code name for quality metric values in the quality access units; or a stream identifier for the media content stream representation that is described by the quality access units.
 16. The UE of claim 13, wherein the one or more processors are further configured to: receive multiple quality extension descriptors and associated quality access units that correspond to multiple media content stream representations in a single MPEG-2 TS.
 17. The UE of claim 13, wherein each quality access unit includes at least one of: a number of quality metric values; a size of a quality metric sample field; a code name for the quality metric values; a number of quality metric samples per quality metric value; or a decoding time stamp (DTS) of the media access unit that is described by a quality metric sample.
 18. At least one non-transitory machine readable storage medium having instructions embodied thereon for receiving Moving Picture Experts Group (MPEG)-2 streaming video quality information at a user equipment (UE), the instructions when executed cause the UE to perform the following: receiving, using at least one processor of the UE, a quality extension descriptor from a network element that describes quality metadata in quality access units, the quality access units being associated with one or more media access units in a media content stream representation to be received at the UE; receiving, using at least one processor of the UE, from the network element the quality access units in a Moving Picture Experts Group (MPEG)-2 transport stream (TS) with the media access units in the media content stream representation; and extracting, using at least one processor of the UE, the quality metadata from the quality access units in the MPEG-2 TS based on the quality extension descriptor, wherein the quality metadata is used during playback of the media access units at the UE.
 19. The at least one non-transitory machine readable storage medium of claim 18, further comprising instructions which when executed by the at least one processor of the UE, cause the UE to perform the following: providing the media access units and the quality metadata to a media content player of the UE to initiate the playback of the media access units, wherein the media content player is configured to adapt at least one of: a media content bitrate, a resolution or a frame rate based on the quality metadata.
 20. The at least one non-transitory machine readable storage medium of claim 18, wherein the quality extension descriptor is received at the UE from the network approximately every 100 milliseconds (ms), wherein the quality extension descriptor is included in a program map table (PMT).
 21. The at least one non-transitory machine readable storage medium of claim 18, further comprising instructions which when executed by the at least one processor of the UE, cause the UE to perform the following: decoding, at the UE, a quality access unit before a corresponding media access unit is fetched from the network element 